Effect of Addition of PVA/PG to Oil-in-Water Nanoemulsion Kojic Monooleate Formulation on Droplet Size: Three-Factors Response Surface Optimization and Characterization

Nanosystems with potential application as carriers for skin depigmenting actives

Hyperpigmentation is a skin disorder characterized by excessive production of melanin in the skin and includes dyschromias such as post-inflammatory hyperchromias, lentigens, melasma and chloasma. Topical products containing depigmenting agents offer a less aggressive treatment option for hyperpigmentation compared to methods like chemical peels and laser sessions. However, some of these agents can cause side effects such as redness and skin irritation. Encapsulating these actives in nanosystems shows promise in mitigating these effects and improving product safety and efficacy. In addition, nanocarriers have the ability to penetrate the skin, potentially allowing for targeted delivery of actives to the affected areas. The most commonly investigated nanosystems are nanoemulsions, vesicular nanosystems and nanoparticles, in which different materials can be used to generate different compositions in order to improve the properties of these nanocarriers. Nanocarriers have already been widely explored, but it is necessary to understand the evolution of these technologies when applied to the treatment of skin hyperchromias. Therefore, this literature review aims to present the state of the art over the last 15 years on the use of nanosystems as a potential strategy for encapsulating depigmenting actives for potential application in cosmetic products for skin hyperchromia. By providing a comprehensive overview of the latest research findings and technological advances, this article can contribute to improving the care and quality of life of people affected by this skin condition.

Development of Emulsions Containing L-Ascorbic Acid and α-Tocopherol Based on the Polysaccharide FucoPol: Stability Evaluation and Rheological and Texture Assessment

The main function of vitamin C, as an antioxidant, is to combat free radicals and prevent premature aging, smoothing wrinkles and expression lines. In addition, it acts directly on depigmentation and prevention of blemishes on the skin. In this study, natural oils (30 wt.%) and α-tocopherol (2.5 wt.%) containing oil-in-water (O/W) emulsions stabilized with the bacterial fucose-rich polysaccharide FucoPol were formulated, adding L-ascorbic acid as an antioxidant. The optimized formulations were obtained with 8.0 wt.% L-ascorbic acid for the Olea europaea oil formulation (C1) with a ƞ value of 2.71 Pa.s (measured at shear rate of 2.3 s−1) and E24 = 96% and with 15 wt.% L-ascorbic acid for the Prunus amygdalus dulcis formulation (C2) with a ƞ value of 5.15 Pa.s (at a shear rate of 2.3 s−1) and E24 = 99%. The stability of the FucoPol-based formulations was investigated over 45 days at 4 °C, 20 °C, and 30 °C. The results showed that all formulations maintained the organoleptic characteristics, with pH variations (5.7–6.8 for C1, and 5.5–6.03 for C2) within the regulations for cosmetic products (4 ≤ pH ≤ 7). The accelerated stability tests proved the formulations’ stability at 4 °C with EI = 95% for C1 and EI = 100% for C2. The rheological assessment demonstrated that the formulation presents a shear-thinning and liquid-like behavior. Regarding textural parameters, formulations C1 and C2 displayed an increase in firmness and consistency with similar spreadability during the shelf life. These findings further demonstrate FucoPol’s functional properties, acting as an emulsifier and stabilizer polysaccharide in cosmetic formulations containing L-ascorbic acid.

Cosmetic emulsion based on the fucose-rich polysaccharide FucoPol: Bioactive properties and sensorial evaluation

In this study, the physicochemical characteristics, bioactive properties, and sensorial evaluation of a O/W cosmetic formulation containing FucoPol, a fucose-containing bacterial polysaccharide, were assessed. The stability of the FucoPol-based cream, named F-cream, was demonstrated over a period of 2 months at different temperatures (4, 20 and 30 °C), during which it maintained the organoleptic characteristics and pH (5.88-6.19), with minimal variations on the apparent viscosity. Furthermore, no breaking mechanisms occurred upon centrifuging the samples (accelerated stability test) kept at 4 °C and at 30 °C for 60 days. The F-cream presented a shear-thinning and solid-liquid behavior consistent with its envisaged use for topical applications, proving to be a suitable candidate for an anti-aging application due to its antioxidant capacity and effective photoprotection, maintaining cellular preservation. Moreover, the formulation was proven non-cytotoxic for HaCaT cells at concentrations between 0.78 and 12.5 mg/mL, promoting HFFF2 cell migration (46-70 % of wound closure) at a concentration of 2.5 mg/mL, and HaCaT cell migration at a concentration of 10 mg/mL (95-98 % of wound closure). Upon application over the skin, the F-cream provided a hydration and softness with desired spreadability with no residues after application. These findings show that FucoPol has good potential to be used as a functional and/or active ingredient in cosmetic formulations, forming an emulsified cream with appealing sensorial properties that can act as a moisturizer with photoprotection, antioxidant, and regeneration properties.

Formulation of the Polysaccharide FucoPol into Novel Emulsified Creams with Improved Physicochemical Properties

Driven by the customers' growing awareness of environmental issues, the production of topical formulations based on sustainable ingredients is receiving widespread attention from researchers and the industry. Although numerous sustainable ingredients (natural, organic, or green chemistry-derived compounds) have been investigated, there is a lack of comparative studies between conventional ingredients and sustainable alternatives. In this study, olive oil (30 wt.%) and α-tocopherol (2.5 wt.%) containing oil-in-water (O/W) emulsions stabilized with the bacterial fucose-rich polysaccharide FucoPol were formulated envisaging their validation as cosmetic creams. After formula composition design by Response Surface Methodology (RSM), the optimized FucoPol-based emulsion was prepared with 1.5 wt.% FucoPol, 1.5 wt.% cetyl alcohol, and 3.0 wt.% glycerin. The resulting emulsions had an apparent viscosity of 8.72 Pa.s (measured at a shear rate 2.3 s^-1) and droplet size and zeta potential values of 6.12 µm and -97.9 mV, respectively, which are within the values reported for cosmetic emulsified formulations. The optimized formulation displayed the desired criterium of a thin emulsion system, possessing the physicochemical properties and the stability comparable to those of commercially available products used in cosmeceutical applications.

Ananas comosus Peels Extract as a New Natural Cosmetic Ingredient: Oil-in-Water (O/W) Topical Nano Cream Stability and Safety Evaluation

Ananas comosus peels (AcP) are among the agro-industrial biomasses contributing to a significant volume of waste in Malaysia. Thus, the AcP extract (AcPE) may prove useful for other applications, such as an ingredient in a nanocream for controlled delivery for dermal application. Therefore, this study aimed to develop an oil-in-water (O/W) nanocream using ingredients derived from the AcPE and test its stability alongside safety evaluation. The extract is a rich source of polyphenolic compounds viz., catechin, quercetin, and gallic acid. The study discovered that the optimized AcPE nano cream was stable against coalescence during the accelerated test but was influenced by Ostwald ripening over 6 weeks of storage at 4°C. Safety assessments affirmed the AcPE nano cream to be free of microbial contamination and heavy metals. The findings conveyed that the A. comosus nano cream is a good cosmetic ingredient and may contribute to the cosmeceutical industry's new and safe topical products.

Application of Blue Honeysuckle Powder Obtained by an Innovative Method of Low-Temperature Drying in Skincare Face Masks

Traditional technologies applied for obtaining plant raw materials for cosmetic production are based primarily on high-level processing, which is reflected in the qualitative composition of the resulting materials. By using low-temperature drying, it is possible to retain in the raw materials a range of valuable ingredients. In this study, blue honeysuckle powder was used as an ingredient of cosmetic face masks. The stability of the masks was evaluated. Dynamic viscosity, yield point and texture analysis of the cosmetics was performed. The color of the emulsions and the level of skin hydration after face mask application was determined. Emulsions were found to be stable. A decrease in dynamic viscosity of the emulsions as a function of increasing concentrations of the additive and under the conditions of rising rotational speed were observed. Similarly, an increase in the concentration of blue honeysuckle in the emulsions resulted in a decrease in the value of the yield point. Based on the results, it can be stated that the addition of blue honeysuckle caused a decrease in hardness of the masks, while the opposite trend was observed for adhesive force. It was found that an increase in the concentration of blue honeysuckle gave a reddish-yellow color to the samples. Corneometric assessment confirmed proper skin hydration after the application of the emulsions.